Protective Effect Of Clostridium Butyricum And Glutamine On Intestinal Tract Of Newborn Rats With Necrotizing Enterocolitis

Objectives:To investigate the effect of the different doses of Clostridium butyricum and Glutamine on the expression of VEGF、VEGFR-2、PCNA and Claudin-2on intestinal tissue of neonatal rats with NEC. To explore the protection mechanism of C.butyricum and Glu in inhibiting intestinal injury of neonatal SD rats with NEC, and to compare the effects of two drugs, in order to provide the theory basis for clinical prevention and treatment of NEC.Methods:72neonatal Sprague-Dewley(SD) rats at the age of48hours were selected, and the weight of each rat was about5.0-8.0g. They were randomly selected and seperared from their mothers, both male and female were not limited. They were divided into6groups. Contro group (n=12):rats without intervention were given artificial feeding with self-control milk; Model group(n=12):rats were given artificial feeding with self-control milk, and were given cold exposure after hypoxic-reoxygen twice a day for3days; Intervention groups1:rats were dealt with hypoxia、cold stress and treated with Gln (0.3g/kg/day,1time/day) mixed with the milk; Intervention groups2:rats were dealt with hypoxia、cold stress and treated with C.butyricum(0.2g/kg/day,3time/day)mixed with the milk; Intervention groups3:rats were dealt with hypoxia、cold stress and treated with C.butyricum(0.4g/kg/day,3time/day)mixed in the milk. Intervention groups4:rats were dealt with hypoxia、 cold stress and treated with C.butyricum(0.8g/kg/day,3time/day)mixed in the milk. Then the expressions of PCNA、VEGF and claudin-2protein were detected by the immunohistochemical test(two step method), and the expression of VEGFR-2was also detected by the reverse transcription polymerase chain reaction. SPSS17.0statistical analysis software was used and a=0.05, P<0.05was statistically significant.Results:1.Clinical manifestations:In control group neonatal rats had normal diet every day, and no abdominal distension and gastric retention were found. Their weight gain and activitity were normal. Neonatal rats of model group began to appear different degrees of lethargy, abdominal distention, diarrhea, decreased activity, slow in reacting, pale skin, skin temperature decrease, even breathing rhythm changed and so on. Compare with rats in model group, the symptoms of rats in4intervention groups occurred later and obviously lighter.2. The change of weight and the grades of intestinal tissueThe weight gain and the grades of intestinal tissue was normal in Control group; The body weight of rats in the model group decreasded and the damage of intestinal tissue was serious,the average intestinal tissue pathology score was more than3points; The body weight of rats in all4intervention groups decreasded and intestinal tissue damage was obviously lighter than that of rats in model group;the negative growth of weight and intestinal tissue pathology score of rats in model group was obviously higher than that of rats in control groups and intervention groups(P<0.0033); Among the intervention groups, no significant difference was found(P>0.0033), except the weight gain beween intervention group1and intervention group2、3and4.3.The expression of VEGF、VEGFR-2、Claudin-2protein and PCNA in intestinal tissue.(1) There was less expression of VEGF、Claudin-2protein and VEGFR-2in intestinal tissue of rats in control group, but the expression was obviously higher in model group, the expression of those of rats in4intervention groups was obviously lighter than those in model group; but was obviously higher than those in control group and intervention groups (P<0.0033); compared with intervention groups, the expression of those in control group was obviously lighter(P<0.0033); compared with intervention groups2、3、4, expression of those in intervention group1was obviously lighter(P<0.0033); Among the intervention group2、3、4, no significant difference of expression was found(P>0.0033)。(2) The expression of PCNA in control group was significantly higher, expression of those of rats in4intervention groups was obviously lighter, and expression of those in model group was lightest;expression of those in model group was obviously lighter than those in control groups and intervention groups (P<0.0033);compared with intervention groups,expression of those in control groups was obviously higher(P<0.0033); there was no significant difference among the intervention group2、3、4(P>0.0033)。Conclusions:1. When the rats suffered from NEC, immature intestinal mucosa was damaged,and the speed of epithelial cells proliferation of intestinal mucosa was slow, intestinal mucosal mechanical barrier function was impaired, permeability increased, and the amount of new pathological blood vessels was increased, and the expression of PCNA was decreased, the expression quantity of VEGF、Claudin-2protein、VEGFR-2was increased.2. Exogenous supplement of C.butyricum and Gln could reduce the expression quantity of VEGF、Claudin-2protein and VEGFR-2in intestinal tissue of neonatal rats with NEC,in order to protect neonatal rats with NEC. Compared with the intervention of C.butyricum, the effect of Gln intervention was better, and there was no significant difference of effect among difference doses of C.butyricum.